Bovine Viral Diarrhea (BVD)
what time of gestation would a fetus need to be exposed to BVD for abortion occur
2-8.5 months
what time of gestation would a fetus need to be exposed to BVD for birth defects be produced
3-6 months
when should MLV be given to cows, bulls and heifers before breeding
30-45 days prior
how long should a producer isolate any new additions away from the breeding herd for
30-45 days, allow TI to clear infection
what days of gestation would a fetus need to be exposed to BVD to become a PI
40-120 days
Another common misconception of BVD is PI calves are thin, have rough hair coats and are poor-doers however _____% will appear normal
50
common misconception of BVD is that calves are PI because their dam is a PI, what % of calves come from PI dams
7
what percent of PI calves are a result of a PI female giving birth to a PI calf
<10%
a female (non-PI) becoming infected with BVD during days of 40-120 of gestation will result in a PI calf. This method represents what percent of PI calves
>90%
Reproductive problems, BRD, and immune suppression are associated with what disease
BVD
________ may become TI with reduced _____ and _________ semen
Bull, fertility, infected
what type of test is used for BVD
PCR
A PI female will always give birth to a ____ calf
PI
a person born with the flu virus and carries the virus until death, always spreading to others
PI
by vaccinating, your goal is to try to prevent ____ and ____
PI, TI
when bringing in non home raised pregnant replacements you want to know their ________ status and must test their _________ shortly after birth
PI, calves
to aid in control and prevention of BVD a producers should test all new additions for ____ status and __________
PI, isolate
a person with the flu virus-has the virus, spreads to other persons then becomes non-infected
TI
calves become _______, may develop ________ and ____________
TI, pneumonia, scours
What are the two genotypes of BVD
Type 1 and Type 2
methods of transfer
aerosol saliva tears reproductive fluids semen
what time of gestation would a fetus need to be exposed to BVD for the fetus to appear normal
after 5 months
how many doses of MLV should heifers receive before weaning to help prevent BVD
at least 2
which test sample is more accurate
blood
What are some congenital abnormalities that would appear at 120-180 days of pregnancy
cataracts hydrocephalus cerebral hypoplasia hypotrichosis-> no hair
____________ and _______ may become TI, results in reduced __________
cow, calf, fertility
BVD has the largest negative impact on what type of herd from a reproductive standpoint?
cow-calf
BVD infects the unborn fetus during days 40-120 of gestation -> fetus doesn't have a working immune system-> BVD is recognized as being normal -> calf's immune system never recognizes the virus as being foreign
creation of the PI calf
What are the two biotypes of BVD
cytopathic noncytopathic
The PI must be exposed to a _________ _______ of the virus to set off the mucusal disease
cytopathic strain
when bringing in pregnant cows the best way to prevent and control BVD is to test
each calf at birth
what two samples can you send in for the BVD test
ear notch blood sample
if a producers finds a PI in a new addition what should he do
eliminate it
A PI calf is constantly ____________ herdmates to BVD at all time
exposing
what are 3 ways BVD can enter a herd
fence-line contact with neighbors wildlife replacement females and bull
if infected with BVD during days 1-40 of pregnancy what is the outcome of the pregnancy
fetal loss
the key is to __________ and __________ PI animals and __________ make PI calves
find, remove, NOT
What other diseases typically have ulcers caused by mucus
foot and mouth vesicular stomatitis blue tongue chemical burns mature/poor forage quality
A PI calf has a _____ risk of dying early in life
greater
The PI calf with shed extremely _______ concentration of the BVD virus
high
a pregnant females fetus may become__________
infected
List the reproductive outcome possibilities of BVD
infertility Early Embryonic Death Abortion Produce PI Birth defects normal
why is there not treatment for BVD
its a virus, antibiotics don't have an effect
PI calves will contain a ______ amount of the virus in almost all tissues compared to TI
large
PI animals are the way the BVD is ____________ in cattle population
maintained
PI calves will result in __________ PI calves being made and delivered the next calving season
more
BVD is a __________ disease
mucosal
mouth, penile, and tongue ulcers are typical signs of what type of disease
mucosal
what are the two things a producer must do to control and prevent BVD
must keep PI and TI animals from entering the herd and must keep PI animals from being produced
If a calf tests negative for PI then it's mother must be
negative PI
Can you tell by just looking at a calf if it is PI
no
Is diarrhea a common sign of BVD
no
will a PI ever become non-infected
no
will a TI cow test positive
no
PI is from a _____________ BVD infection
noncytopathic
What is the treatment for BVD
none
how many operations who had tested during the previous 3 years had 1 or more PI calves
none
if exposed to BVD from 180 days to 280 days (parturition) what effect will there be
none
1 in 10 herds who had not tested calves for PI during the previous 3 years had at least ____ positive
one
immunosuppression will increase the risk of disease to other___________, especially ___
pathogens, BRD
PI
persistently infected
What is the most dangerous type of infected animal
pi
most vaccine claims "aid in prevention/reduction" of _____ BVD
reproductive
BVD misconeption is that the greatest cost associated with a PI calf is the death of that calf but what is the actual greatest cost associated with BVD
reproductive lost (lower pregnancy %, increased abortions, increased calf mortality)
where is the virus shed
saliva nasal excretions urine feces
PI bulls will shed high volumes of BVD in _____ thereby providing another method of exposure
semen
One common BVD misconception is that PI calves will be killed by a MLV vaccination, MLV vaccinations may cause a PI calf to become _____ or ______, but less than 100% are negatively affected
sick, die
TI
transiently infected
T/F BVD can directly cause pneumonia
true
T/F BVD can cause immunosuppression
true
to control and prevent BVD a producers should keep its cow herd well
vaccinated
how many PI calves live to be of breeding age
very few
can both TI and PI animals expose the herd to BVD
yes
does BVD prevent conception
yes
would a females cycle be slightly increased in length if infected with BVD and conception did not occur
yes
What percent live to be 18 months
~20%
